Peripheral Tunnels do not Eliminate Earthquake Threats to Water Supply;
Fattening the Levees is a More Effective Solution
SACRAMENTO, CA – Restore the Delta (RTD), a coalition opposed to the Brown Administration’s rush to construct massive Peripheral Tunnels to take millions of
acre-feet of water from the Delta, mainly to benefit mega-growers on the west side of the San Joaquin Valley, today released a fact sheet on earthquakes being a greater risk to the existing canals, dams and local pipes than to Delta levees. Fattening the levees is a far more effective solution than building the peripheral tunnels.
“The existing water project canals, which would continue to be part of the water export system, run through the San Joaquin Valley, and are more at risk than the Delta levees,” said Barbara Barrigan-Parrilla, executive director of RTD. “Californians should work together to build a more seismically resistant Delta that will protect water exports, other critical infrastructure, and save lives — all at a lower cost. Rather than a huge investment in faraway tunnels, let’s instead make the levees in the Delta more resilient and prepare all California communities to be less reliant on imported water.
“Developing regional water supplies provides a more reliable water supply. The best way to prevent earthquake disruption is to invest in local water solutions, including increased comprehensive water conservation, maximizing wastewater reuse and groundwater recharge, while capturing storm water and rainwater, graywater, and fixing leaky local pipes. Cleaning up local aquifers and providing local jobs for local water makes economic sense.
“Earthquake risk mythmaking serves water exporters’ interests. Water exporters misrepresent the risk of earthquakes to generate support for the Peripheral Tunnels.
Powerful water interests control California’s water resources and the message about the state’s water. Since the devastation of hurricane Katrina, these powerful forces have stoked fear of flooding and earthquakes to make a case for transforming a unique, beautiful, productive Delta region into a permanent way station for water going somewhere else. But the Peripheral Tunnels will not protect California’s water supply from earthquake,” said Barrigan-Parrilla.
RTD has put together a fact sheet about earthquakes and the Delta. Below is a sample of the myths and facts regarding the threats of Earthquakes in the Delta. To view the full fact sheet, go here: https://www.restorethedelta.org/wp-content/uploads/2010/06/RTD-Earthquake-Fact-Sheet-final.pdf
Myth: The peripheral tunnels will protect California’s water supply from earthquakes.
FACT: Earthquakes would hit the existing water transfer conveyance in other parts of California harder than they would hit the Delta. The earthquake threat to the Delta is minimal. The Hayward Fault is 40 miles from the Delta’s center. But the State Water Project (SWP) and federal Central Valley Project (CVP) cross right over high-risk fault areas, from Coalinga south to LA, including the San Andreas Fault. Cement canals in the southern part of the state are more vulnerable to earthquakes than Delta levees.
Other parts of the State Water Project are equally or more vulnerable to earthquake than the Delta: the California aqueduct, which overlies the Coast Ranges – Central Valley thrust fault; the San Luis Reservoir, which is acknowledged by DWR and the Bureau of Reclamation to have a “seismic deficiency,” the crossing of the San Andreas fault in the Tehachapis, and many elements of the water distribution system in Southern California.
- The San Luis Dam sits on an earthquake fault, and dam failure would damage or destroy several miles of the California Aqueduct that provides Delta water to Los Angeles, as well as result in flooding in downstream Delta communities like Stockton. (See Earthquake Shaking Map from California Resources Agency.)
- The relative risk from thrust faults at Kettleman City and Coalinga is shown in the 2008 California Geologic Survey map of Earthquake Shaking Potential for California.
Does it make sense to spend upwards of $50 billion to reinforce the first 35 miles of the 400-mile water export system, when earthquake threat is equal or higher in other parts of the system? The astronomical cost of the peripheral tunnels threatens investment in a more resilient, and disaster resistant system.